Serum C-Reactive Protein to Monitor Treatment Response in Cystic Fibrosis Pulmonary Exacerbations


Background: Treatment monitoring for Cystic Fibrosis (CF) pulmonary exacerbations has been shown to be sub-optimal currently. Studies have revealed that C-Reactive Protein (CRP) is a potential bio-marker of disease activity in CF pulmonary exacerbations. This project aims to determine the clinical viability of CRP for monitoring treatment response during CF pulmonary exacerbations.

Hypothesis: A lack of significant decrease of CRP by day 5 of pulmonary exacerbation treatment predicts treatment failure.

Methods: Patient hospitalization data was extracted from the patient care information system and a retrospective chart review was conducted. Exclusion criteria was based availability of data, lung transplant recipients and interruption of antibiotic therapy. Treatment failure was compositely defined as the prolongation of therapy, change in antibiotic regime during hospitalization and failure of recovery to baseline lung function after treatment.

Results: Patients’ CRP levels were successfully tracked throughout treatment and 44% of patients were found to have an initial increase in CRP levels after initiation of treatment. Lung function data was found to have a median 7% increase in absolute FEV1 % predicted after treatment. 39% of patients were found to have normal white blood cell counts, but above normal CRP levels during admission.

Conclusion: The results indicate potential clinical viability of CRP measurements; however, optimization and further analysis is needed to accept or reject the hypothesis. Further exploratory analysis is needed to explain initial increases in CRP levels after treatment initiation.